When you send in a request with available dates, it is possible that others have requested at the same time! When your request was pending, the host may have been considering 10 applicants?!
Yes, not the same property, most likely! - Two different properties, one for 6 & one for 8! Of course the 8 bed costs more!
I don't see what your problem is!
- Can you STILL send a request for the cheaper, 6 bed Blue Dream??? Are the dates free on the calendar? If so, try again to book.... If this listing is not showing, then someone must have booked it whilst you were enquiring! (I've had 2x enquiries for the same dates, & had to choose which guest I prefer!)